Fate and disposition of pfas in broiler chickens during a 6-week exposure period

Authors: Snyder, Abigail; Smith, David; Lupton, Sara

Submitted to: International Symposium on Halogenated Environmental Organic Pollutants
Publication Type: Abstract Only
Publication Acceptance Date: 8/16/2022
Publication Date: 10/10/2022
Citation: Snyder, A.W., Smith, D.J., Lupton, S.J. 2022. Fate and disposition of pfas in broiler chickens during a 6-week exposure period. International Symposium on Halogenated Environmental Organic Pollutants. Abstract.

Interpretive Summary:

Technical Abstract: Introduction: Per- and polyfluorinated alkyl substances (PFAS) consist of over 12,000 different chemical entities used as surfactants in industrial and consumer products. PFAS contaminants have been measured in agricultural animals and detected across the food web. Concentrations of PFAS have been measured in poultry products from market basket surveys, and studies exposing poultry to acute doses of PFAS show accumulation and translocation of PFAS within tissues and eggs. However, there are few data describing the fate and disposition of PFAS in poultry during lifetime exposures to environmental levels of PFAS in water. The fate and disposition of a suite of 25 PFAS compounds was determined in broiler chickens during 6 weeks of exposure. Materials and Methods: Fifty-six straight run broiler chicks, distributed equally among 4 pens, were provided water containing 100 ng/L of 13 perfluorocarboxcylic acids (PFCAs; 4 – 18 carbons) and 12 perfluorosulfonates (PFSAs; 4 – 13 carbons) starting at 2 days of age to maturation at 6 weeks. A control pen containing 11 birds received water with undetectable levels of PFAS. On a weekly basis, two birds from each pen were sacrificed (8 treated and 2 controls at weeks 1-4) except for weeks 5 and 6 when 3 birds from each treated pen were harvested (not including control pen). Tissues collected at harvest included blood (plasma), liver, bile, kidney, breast and thigh muscle, fat, reproductive tract, small intestine, large intestine, ceca, pancreas, upper GI (gizzard, proventriculus, and crop), brain, heart, lung, skin, and spleen. All samples are being analyzed via in-lab validated methods by ultra-performance liquid chromatography – tandem mass spectrometry (UPLC-MS/MS) with matrix matched curves and QA/QC procedures. Limits of detection (LOD) were calculated for each compound; LODs for the PFCAs ranged from 0.10 – 2.03 ng/mL and the PFSAs ranged from 0.11 – 1.09 ng/mL. Percent recovery was calculated for each compound; recoveries for the PFCAs ranged from 96% - 123% and the PFSAs ranged from 98% - 129%. Results: The summed PFCA data for plasma from weeks 1 - 6 ranged from 1,268 ± 385 ng/L to 2,306 ± 303 ng/L, respectively. Of the 13 PFCAs analyzed, perfluorobutanoic acid (PFBA), perfluorooctanoic acid (PFOA), perfluorononanoic acid (PFNA), and perfluorodecanoic acid (PFDA) were detected in plasma. However, PFBA was non-detectable by week 5. The summed PFSA concentrations for weeks 1 - 6 in plasma ranged from 2,271 ± 442 ng/L to 7,384 ± 391 ng/L, respectively. Perfluorohexanesulfonic acid (PFHxS), perfluoroheptanesulfonic acid (PFHpS), perfluorooctanesulfonic acid (PFOS), 3-(trifluoromethyl) tetradecafluoro-1-heptanesulfonic acid (3Me-PFOS), and 6-(trifluoromethyl) tetradecafluoro-1-heptanesulfonic acid (6Me-PFOS) were present in plasma above the LOQ at each of the six sampling points; at week 2, there were quantifiable levels of PFPeS, and in weeks 5 and 6 there were quantifiable levels of PFNS in some samples. Bioaccumulation factors (BAFs) were calculated at the end of each exposure week for the quantifiable compounds. The BAFs for the PFCAs ranged from 0.20 – 2.78 with the highest value being PFNA at week 5. The BAFs for the PFSAs ranged from 0.78 – 3.54 with the highest value being PFHpS at week 5. Based on BAFs, PFNA is the PFCA with the highest potential to accumulate, while for the PFSAs, PFHxS, PFHpS, and 3Me-PFOS have similar accumulation potentials. PFBA was observed to absorb quickly over the first week and then plasma concentrations decreased over the following 5 weeks of exposure, indicating quick elimination from the plasma. Conclusions: The data suggests absorption and accumulation of some PFAS compounds (4 and 6 – 9/10 carbon chain length) into plasma of broiler chickens over 6 weeks of exposure and growth. Edible tissues (liver, muscle, skin, gizzard) continue to be extracted an